rs796051855

chr7-258645-G-A

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PVS1_Moderate PM2 PP3_Strong PP5

The NM_020223.4(FAM20C):c.1446-1G>A variant causes a splice acceptor change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000289 in 1,384,546 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 2/2 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (no stars).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000029 (0 hom.)
• Consequence: FAM20C NM_020223.4 splice_acceptor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 9.09

Genes affected

FAM20C (HGNC:22140): (FAM20C golgi associated secretory pathway kinase) This gene encodes a member of the family of secreted protein kinases. The encoded protein binds calcium and phosphorylates proteins involved in bone mineralization. Mutations in this gene are associated with the autosomal recessive disorder Raine syndrome. [provided by RefSeq, Apr 2014]

ACMG classification

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

• PVS1: Splicing variant, NOT destroyed by nmd, known LOF gene, truncates exone, which is 0.011618747 fraction of the gene. Cryptic splice site detected, with MaxEntScore 5.9, offset of 1, new splice context is: tctgcttttcttctggaaAGttt. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 7-258645-G-A is Pathogenic according to our data. Variant chr7-258645-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 1030.Status of the report is no_assertion_criteria_provided, 0 stars. Variant chr7-258645-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
FAM20C	NM_020223.4	c.1446-1G>A		splice_acceptor_variant		ENST00000313766.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
FAM20C	ENST00000313766.6	c.1446-1G>A		splice_acceptor_variant		1	NM_020223.4	P1
FAM20C	ENST00000515795.1	n.1103-1G>A		splice_acceptor_variant, non_coding_transcript_variant		1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000289 AC: 4 AN: 1384546 Hom.: 0 Cov.: 31 AF XY: 0.00000146 AC XY: 1 AN XY: 683222

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000371

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: no assertion criteria provided

Submissions by phenotype

Lethal osteosclerotic bone dysplasia Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Nov 01, 2007

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.33
Cadd	Pathogenic	34
Dann	Uncertain	0.99
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.82
FATHMM_MKL	Pathogenic	0.99	D
MutationTaster	Benign	1.0	D
GERP RS		4.5

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.96
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.87		Position offset: 2
DS_AL_spliceai		0.99		Position offset: 1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs796051855; hg19: chr7-298611;